Scientific relevance. The immunoglobulin A (IgA) impurity content in parenteral human immunoglobulins should be determined in accordance with the State Pharmacopoeia of the Russian Federation by kinetic nephelometry, radial immunodiffusion, or enzyme immunoassay (ELISA) with a reference standard. The International Standard (IS) for the content of IgA is certified using gravimetry and radial immunodiffusion. However, neither of the existing standards for the content of IgA in human immunoglobulins is currently certified using all three compendial methods. This prevents analysts from comparing test results obtained by different methods and may lead to an underestimation of the IgA content in human immunoglobulins.Aim. This study aimed to determine the procedure for the development, certification, and use of a pharmacopoeial reference standard (RS) for the content of IgA in human immunoglobulins.Materials and methods. The authors studied candidate RSs for the IgA content derived from human plasma for fractionation. The IgA content determination involved kinetic nephelometry, radial immunodiffusion, and ELISA, as well as commercial test kits and the IS. The authors quantified the IgA impurity in samples of commercial human immunoglobulins from various manufacturers. The data analysis involved descriptive statistics and variance analysis using Microsoft Excel and Statistica 10.Results. The authors established a pharmacopoeial standard with a certified IgA content of 1.98 mg/mL (expanded uncertainty, 0.44 mg/mL; coverage coefficient, k=2; confidence level, 95%) for IgA impurity quantification in human immunoglobulins by radial immunodiffusion and ELISA and that of 1.31–2.64 mg/mL (expanded uncertainty, 0.67 mg/mL; coverage ratio, k=3; confidence level, 99%) for intralaboratory quality control of IgA impurity quantification by kinetic nephelometry, radial immunodiffusion, and ELISA.Conclusions. The pharmacopoeial standard developed in the study has been included in the register of standards of the State Pharmacopoeia of the Russian Federation as the Reference Standard for the Content of Immunoglobulin Class A (IgA) (Registry No. 3.1.00454). The pharmacopoeial standard is intended for the standardisation of analytical methods for the-determination of the IgA impurity content in parenteral human immunoglobulins.
Materials for the development and certification of a standard sample for anti-D antibody contents in human immunoglobulin drugs are presented. Preparation of the negative component of the standard sample from blood plasma of Rh-positive group IV(AB) donors without anti-D antibodies; the positive component, from blood plasma of Rh-negative group IV(AB) donors is justified. The immunoglobulin should be concentrated to produce a solution with protein contents in the range 48 – 51 mg/mL and anti-D antibody titer 1:8. Flow cytofluorimetry is shown to allow standardization of the preparation of the standard sample positive component.
Documentation for standardization of the method for determining hemagglutinins (HAs) in human immunoglobulin preparations used in Russia is presented. The proposed general pharmacopoeial monograph "Determination of anti-A and anti-B hemagglutinins in medicinal preparations of human immunoglobulin" allows quality control of human immunoglobulin preparations for HAcontent using indirect hemagglutination under standard conditions. The positive and negative components of the domestic standard sample (SS) of HAs contain 1:32 anti-A and 1:16 anti-B, respectively; less than 1:2 anti-A and -B; and 1:64 components of the HA content limit. Introduction of the SS for contents of anti-A and anti-B HAs into pharmacopoeial practice would ensure that results obtained in various ranges are accurate and enable the quantitative contents of the corresponding HAs in human immunoglobulin preparations to be determined.
The safety issues of human intravenous immunoglobulin preparations are particularly important in modern pharmacotherapy for immunodeficiencies, hematologic and neurologic diseases, like as at transplant centers. Upon massive infusions of these media some complications are detected that are associated with spontaneous activation of complement system accompanied by production of anaphylatoxins, as well as activation of kallikrein/kinin, plasmin, and blood coagulation systems, changed blood rheology, initiation of intravascular hemolysis. For distinct groups of patients, these complications may be due to presence of some anti-erythrocyte antibodies (e.g., anti-A and anti-B haemagglutinins, anti-D antibodies) in the intravenous human immunoglobulin preparations. In the present review article, we show development of current quality standards for human intravenous immunoglobulins based on determination of antibody contents. Antibodies to erythrocytes represent a special safety index aiming to minimize risk of possible adverse effects connected with transfusions of human blood preparations. Different haemagglutination tests were compared to assess contents of anti-A, anti-B haemagglutinins and anti-D antibodies for specific safety of human intravenous immunoglobulins. Analysis of haemagglutination techniques for evaluation of human intravenous immunoglobulin preparations revealed their relative advantages and disadvantages. Various modifications of the methods are discussed, thus allowing to optimize process of quality control for these preparations based on detection of haemagglutinins and anti-D antibodies. We demonstrate a necessity to adjust regulations and to improve evaluation techniques for haemagglutinin determination in human immunoglobulin preparations at amounts of 100 mg/ml of protein. Special features of Russian national quality standards for human immunoglobulin preparations are considered with respect to assessment of haemagglutinins and anti-D contents. One may conclude that haemagglutination methods present the most informative and economically substantiated approach when assessing specific safety of human intravenous immunoglobulins by measuring contents of anti-A, anti-B haemagglutinins, and anti-D antibodies.